E3 SUMO-protein ligase PIAS4 is one of several protein inhibitor of activated STAT (PIAS) proteins. It is also known as a protein inhibitor of activated STAT protein gamma (PIASg or PIASy), and is an enzyme that in humans is encoded by the PIAS4 gene. [5] [6]
PIAS4 has been shown to interact with Mothers against decapentaplegic homolog 6, [7] Mothers against decapentaplegic homolog 7 [7] and Lymphoid enhancer-binding factor 1. [8] PIAS4 has been shown to be responsible for the SUMOylation of inhibited Werner syndrome helicase (WRN) trapped on DNA in microsatellite unstable cancer cells. [9]